The present invention relates more particularly to instruments for endoscopic surgery that are adapted to ligate or suture an organ.
Endoscopic surgery covers any operation performed by inserting instruments into the organism via natural orifices or via miniscule incisions, with examination inside the body taking place by means of an optical instrument inserted into the organism by the same means.
It is known that endoscopic surgery provides numerous advantages over conventional surgical techniques in which the surgeon operates by opening the body.
The following advantages may be mentioned in particular:
endoscopic surgery avoids scars; PA1 it is more comfortable for the patient and gives rise to less pain; PA1 it leads to lower consumption of auxiliary medication, in particular analgesics and pain killers; PA1 it enables scarring to take place more quickly; and PA1 it makes quicker discharge possible with consequent shorter stays in hospital, in particular because of the disappearance of the operative and post-operative complications associated with opening the body as is done in conventional techniques. PA1 a tie for ligature or for suture, slidably mounted in the longitudinal channel of a separate tubular endpiece; and PA1 a rigid support including a handle secured to an elongate rod which is provided at its proximal end remote from the handle with a reception cradle suitable for removably receiving the tubular endpiece, and with a through lateral window whereby said cradle opens out to the outside of the support to enable the tie to pass therethrough such that traction exerted on the distal end of the tie relative to the support serves to tighten the ligature or the suture.
Under such conditions, it is now believed that within the next 10 years, 3/4 of gynecological operations and of operations associated with the digestive system will be performed by endoscopic surgery.
Numerous miniaturized instruments have been proposed for that purpose, and in particular forceps, scissors, paddles, electric scalpels, . . . . All such miniaturized instruments are designed to be inserted into the body by means of small-section trocars.
In the particular field of ligatures or sutures for endoscopic surgery, surgeons have various techniques available to them.
These are described, for example, in the document: British Medical Bulletin (1986), Vol. 42, No. 3, pp. 284-295 "Operative pelviscopy", K. Semm.
The first technique referred to as "loop ligature" uses a filament provided at its end with a loop or lasso having a slip knot. To use that ligature, the loop is inserted into the body cavity by means of a trocar and it is engaged on the organ to be ligated, after which it is tightened thereon. The loop can be tightened by means of a knot-pusher instrument.
This can be done by using various instruments that include a rectilinear rod adapted to be engaged in the trocar and including at its proximal end a groove or fork whereby the knot-pusher is engaged on the filament and serves to push against the slip knot so as to tighten the loop during relative displacement between the knot-pusher and the filament. Examples of such conventional grooved or forked knot-pushers are described in the following documents: 1) Obstetrics & Gynecology, Vol. 78, No. 1, July 1991, "A new clinch knot", Peter V. Weston, and 2) Obstetrics & Gynecology, Vol. 79, No. 1, January 1992, "A simple method for ligating with straight and curved needled in operative laparoscopy", Harry Reich et al.
Knot-pushers with a lateral groove or fork suffer from a major drawback: they cause the filament and the loop to twist about their axis; this is because it is necessary, in order to keep the knot in the groove or the fork, to ensure that the filament passes around the axis of the knot-pusher. This phenomenon of the loop twisting increases as the loop is tightened and can therefore cause the loop to be tightened insufficiently.
To facilitate the operation of ligating, proposals have also been made (as shown in accompanying FIGS. 1 and 2) for a knot-pusher 10 that comprises an elongate rectilinear sleeve 12 adapted to be engaged in a trocar T and that possesses a longitudinal channel in which the ligature filament 20 is engaged. The filament emerges at the proximal end 14 of the sleeve 12 in the form of a loop 22 having a slip knot 24. In addition, the sleeve 12 is provided at its distal end 16 with an endpiece 18 fixed on the distal end 24 of the filament 20. Initially, the endpiece 18 is connected to the sleeve 12 via a zone of weakness 19. To use this knot-pusher 10, once the loop 22 has been engaged on the organ to be ligated (as shown in FIG. 2), it suffices to separate the endpiece 18 from the sleeve 12 at the zone of weakness 19 and to move said members apart to tighten the loop 22.
A second technique consists in making the loop of the ligature around the organ during the operation. In that case, the slip knot may be made entirely within the body, by manipulating the filament inside the body cavity, or it may be made outside the body by extracting the strand of filament that has gone round the organ via the trocar, forming the slip knot outside the body, and then putting the knot back into the trocar and thus into the body cavity to tighten the ligature. In that case also, it is generally necessary to use a knot-pusher, at least when the knot is tied outside the body. For that purpose it is possible to use a conventional grooved or forked knot-pusher as mentioned above. Suture filaments mounted on knot-pushers with separable sleeves and endpieces of the type shown in FIGS. 1 and 2 are now also available to surgeons.
A third technique consists in using a suture filament, i.e. a filament provided with a needle, instead of a ligature filament. In that case also, the slip knot may be made inside the body or outside it. The suture may be tightened by means of a conventional forked or grooved knot-pusher. Suture filaments mounted on knot-pushers with separable sleeves and endpieces of the type shown in FIGS. 1 and 2 are also available to surgeons.
The various ligature and suture techniques recalled above are presently in use by surgeons.
However, those techniques do not give total satisfaction.
In particular, it is rather difficult to manipulate grooved or forked knot-pushers as described, for example, in the above-mentioned Obstetrics & Gynecology documents.
A drawback of knot-pushers having a separable sleeve and endpiece and of the type shown in accompanying FIGS. 1 and 2 is that they require bulky packaging adapted to the length of the sleeve. That drawback is particularly inconvenient in that the surgeon is often not in a position to decide on the kind of filament and its diameter, or on the type of needle that needs to be used for ligature or suture purposes until the last moment, thus requiring a full range of kits to be available in the operating theatre all having separable sleeve-and-endpiece knot-pushers fitted with ligature or suture filaments but of different diameters, of different natures, and with respect to the suture filaments, with needles of various shapes, such as rectilinear needles, ski-shaped needles, etc. . . . . That leads to a very considerable volume being required solely for ligatures and sutures. In addition, it should be observed that the sizes of the packages required for such separable sleeve-and-endpiece knot-pushers makes sterilization quite expensive.